(1) Field of the Invention
The present invention relates to new pharmaceutical compositions for the prevention and treatment of allergies. Allergies are a scourge which affects 25% of the world's population. This number is on the increase in connection with growing environmental toxicity (dust, food, motor vehicles). In addition, a person's risk of suffering from allergy is increased if there is a previous family history of allergy.
(2) Prior Art
The biological mechanism of allergies may be described as an abnormally amplified reaction to the entry of an allergen into the body. The following events account for the reaction:
identification of the allergen by the body,
secretion of cytokines in response to allergen penetration,
conversion of Th1 cells into Th2 cells, with the production of clones specific to the antigen,
the Th2 cells synthesize interleukins 4 and 13, responsible for aggravation of the allergic symptoms through an upsurge in IgE synthesis
the terminal phase of the reaction is the release of histamine and serotonin having a recruiting effect on the Th2 clones.
toxic and inflammatory self-maintaining reaction, even without any antigen stimulation.
The antigen-presenting cells (APCs: macrophages, dendritic cells, B-lymphocytes) take part in the reaction of hypersensitivity through basic cell cooperation carrying the immune reaction further. Allergies belong to the nonself class of defense mechanisms. The main allergens are acarids (dust mites) (80%) and pollens (20%).
The self-stimulating reactions of specific APC clones have an effect on the general rate of release of histamine and serotonin leading to an aggravation of the general clinical symptomatology.
The recruitment level of new Ige-secreting cells is thereby increased, facilitating the explosion of clinical signs when a new allergen penetrates inside the body. This can be seen in atopic persons in whom allergic reactions are severe owing to the high level of Th2 clones promoting the synthesis of IgE.
The general reaction observed subsequent to the penetration of the new allergen is not due to its toxicity but simply to the fact that the triggering level of allergic phenomena is very low, helped by other sensitizations.
An allergy is a reaction due to hypersynthesis of IgE immunoglobulins. The inflammatory reaction chiefly affects the respiratory and ENT spheres, with pathological focalization at the nose, lungs and skin. Pathologies associated with the allergy are invalidating and suffer from the lack of efficacy of conventional treatment. There is no preventive strategy and curative means are insufficient or ill used.
The usual treatment of allergic disease consists, during a first phase, of identifying the allergen responsible such as dust mites, pollen, mold, or food. The second phase comprises removal measures. The third phase or treatment phase focuses on the target organ which appears to be symptomatic e.g., ENT treatment for rhinitis, anti-asthmatic treatment if the affected sphere is respiratory, dermatological treatment if the affected areas are skin areas.
In the event of failure of the preceding measures, individual or complementary treatment may be offered through the choice of a specific immunotherapy, i.e. specific pollen, specific acarid, specific mold. The complexity of the treatment instituted makes it difficult to follow. A succession of treatments is a patent factor of failure.